1. Field of the Invention
The present invention relates to a robot.
2. Description of the Related Art
In most typical vertical articulated robots, an arm mounted on a base includes six or seven rotary joints, and portions provided on distal-end sides (robot-hand sides) of the joints are rotated or turned.
The moving range of the hand of such a robot can be widened by increasing the length of the arm. Meanwhile, if the arm is folded so that the hand of the robot is placed in an area near the base, it is necessary to prevent the hand from interfering with the arm. For this reason, the moving range of the hand of the robot is set such as not to include the area near the base.
In recent years, there has been a demand for a robot that can perform more complicated operation and moving range. Hence, the robot is required to operate in a manner such that the hand can be placed both at positions sufficiently distant from the base and positions closer to the base.
As a technique for solving this problem, Japanese Patent Laid-Open Publication No. 2008-272883 discloses a structure for offsetting the rotation axis of an arm in a middle portion of the arm. According to this disclosed technique, even in a state in which the arm is folded, a wide moving range can be ensured while avoiding interference between the arm portions.